An Open-Label Study to Evaluate the Safety, Tolerability and Pharmacodynamics of BPL-003 in Patients With Treatment Resistant Depression

Inclusion criteria

• Diagnosed with Major Depressive Disorder.
• Diagnosed with TRD defined as failure to respond to an adequate dose and duration of at least 2 pharmacological treatments in the past 5 years prior to screening, at least one of which is during the current episode.
• Montgomery-Asberg Depression Rating Scale score ≥24 at Screening.
• Clinical Global Impression - Severity ≥4 at Screening.
• Willing and able to discontinue current pharmacological anti-depressant therapy.
• On current stable dose of pharmacological antidepressant therapy limited to one of 4 SSRIs (Arm B), i.e. either citalopram, escitalopram, sertraline or fluoxetine.

Exclusion criteria

• Current or history of schizophrenia, psychotic disorder including psychotic depression, bipolar disorder, delusional disorder, schizoaffective disorder, or any other severe psychiatric disorder.
• Current personality disorders.
• First-degree family history of schizophrenia, bipolar disorder, delusional disorder, personality disorders or schizoaffective disorder.
• Current alcohol or substance use disorder (other than caffeine or nicotine).
• A participant who at any time, has been unresponsive to ketamine, esketamine, an adequate course of treatment with electroconvulsive therapy, or has received vagal nerve stimulation or deep brain stimulation.
• Suicidal ideation with the intent to act or suicidal behaviour within the 12 months prior to the start of Screening or on Day 1 prior to dosing.
• Suicide attempt and/or self-injurious behaviour within the last 12 months prior to Screening.
• Uncontrolled medical conditions e.g. hypo/hyperthyroidism, diabetes, renal failure.
• Seizure disorder or history of seizures (including febrile seizures).
• Abnormal and clinically significant results on the physical examination, vital signs, electrocardiogram, or laboratory tests at Screening Baseline.
• Any nasal obstruction, blockage, or symptoms of congestion at the time of dosing, that in the Investigator's opinion may interfere with administration of the study drug.
• Currently receiving lithium, antipsychotics, serotonergic drugs (excluding the permitted SSRIs for arm B), psychostimulants, or any other prohibited medication.
• Female patients who are pregnant or lactating, or of childbearing potential and not willing to use adequate forms of contraception.
• Male patients who are sexually active and not willing to using adequate forms of contraception.